CEIG Approval in Tamil Nadu: Electrical Inspectorate Process for Factories and Solar

In Tamil Nadu the Electrical Inspectorate approves drawings before work and inspects installations before they are energised. Under G.O. Ms. No. 98 of 14 October 2024, installations above 650 V are inspected by the Electrical Inspector, and generating units above 10 kVA, solar plants included, must be inspected before commissioning. Lower-voltage consumer installations are self-certified. Filing is online through the state Single Window Portal.

Which installations need the Electrical Inspector in Tamil Nadu?

The Central Electricity Authority's 2023 safety regulations leave the thresholds to each state. Tamil Nadu's Energy Department fixed them in six notifications under G.O. Ms. No. 98 (Energy C2), dated 14 October 2024, published in the Government Gazette and listed on the Inspectorate's site (G.O. 98).

For a factory, this gives three practical consequences. An HT incomer, a transformer or a substation is inspected. A rooftop solar plant above 10 kVA is inspected before commissioning even if it feeds an LT panel. The notification speaks in kVA; confirm with the Inspectorate whether it measures a PV plant by inverter AC rating or by module DC capacity before you size the file. Our Tamil Nadu solar EPC guide places this among the other approvals.

What is the sequence from drawing to energisation?

The Inspectorate's own procedure pages set out the stages:

1. Load sanction from the distribution licensee (the pages name TANGEDCO). Where a generator is to run in parallel with the grid, a no-objection certificate from the licensee is also required.
2. Drawing approval. The applicant fills the online form on the Single Window Portal, uploads the company documents and a brief of the proposal, pays online, and sends four copies of the drawings by speed post to the Inspectorate office. The officer issues the drawing approval online. The stated process time is 5 days under the Tamil Nadu Business Facilitation Rules, 2017. The approving authority depends on the installation's size: Electrical Inspector up to 630 kVA, Senior Electrical Inspector from 630 to 2,500 kVA, Chief Electrical Inspector above 2,500 kVA (drawing approval procedure).
3. Erection by a licensed electrical contractor under the supervision of a person holding a certificate of competency, to the approved drawings and the CEA regulations.
4. Completion report and application for inspection, with the documents below.
5. Inspection and defect report. The Inspectorate states that it will communicate queries within 7 days of receipt, give notice of the inspection date by e-mail and SMS, and issue a defect report or inspection report within two working days of the inspection.
6. Rectification report from you, uploaded online.
7. Safety certificate, which the Inspectorate says it issues within 7 working days of the rectification report (safety certificate procedure).
8. Energisation in consultation with the licensee, and a report of the commissioning date to the Inspectorate. If permission lapses before commissioning, it must be revalidated first.

These are the Inspectorate's stated process times. Your calendar depends on how complete the file is and how many queries come back.

What documents does the file need?

For drawing approval the pages list the company's memorandum and articles, a brief of the proposal, a site plan showing the point of supply and HT routes, a plan and elevation of the substation with clearances, the schematic layout, a sectional elevation of switchgear with erection details, and earthing arrangements. Where a building exceeds 15 m, the planning permit and approved drawings from the local planning authority are added. For a power plant or EHV substation the Inspectorate also asks for soil resistivity, fault-level and step-and-touch-potential calculations (drawing scrutiny page).

For the safety certificate, the list is a request letter, the contractor's completion report in the IS 732 format, the appointment and consent letters of the supervisor holding a competency certificate, a compliance report against the conditions in the drawing scrutiny report, and original test certificates for HV and EHV equipment where digitally signed ones are not available (inspection procedure). Fees are set by G.O. (Ms.) No. 30 Energy (B1) of 1 April 2002 and depend on equipment, so we quote no figure.

The Inspectorate's separate page on generator installations above 10 kW lists a completion report, an equipment list with engine, generator and panel details, the purchase bill, a no-objection letter from the premises owner if the service connection is not in the applicant's name, a copy of the meter card and the fee challan. It does not mention solar, so ask the local office whether the same file applies to a PV plant.

What will the inspector look at on a solar plant?

Regulation 121 of the CEA regulations sets safety requirements for solar installations (regulations). Check these before you apply:

• Clear pathways at least 75 cm wide, with hand rails, for roof access and emergency exit, and walkways between rows or columns for cleaning and maintenance.
• For ground-mounted plant, cables in trenches and fencing not less than 1.8 m high.
• Disconnection switches or circuit breakers in combiner boxes at a readily accessible location, and a manual disconnection switch outside the AC combiner box.
• Phases on the AC side and positive and negative conductors on the DC side identified by different colours; inverters near the periphery and the panels, with ultraviolet-protected DC cable.
• Overload, surge, isolation, earth-fault and insulation-monitoring protection, and a surge protective device in every combiner box.
• Earthing as per the relevant standard, strips interconnected by welding and not bolted, and an adequate number of interconnected earth pits.
• Lightning protection and over-voltage arresters, and fire detection and automatic suppression to the relevant standards.

The CEIG readiness calculator helps you test a file before it goes in, and our CEIG approval guide explains the process in general.

How does CEIG sit alongside the DISCOM process?

They are separate. The Inspectorate decides whether the installation is safe to energise; the distribution licensee decides whether and when to connect it and, for net metering, signs the agreement and installs the meter. In practice the licensee will ask for the safety certificate before synchronisation; we could not confirm the exact document list from a circular of the distribution licensee, so ask the divisional office what it needs in writing. Start both files together, because the licensee's load sanction is the first step in the Inspectorate's own sequence.

How Secured Engineers helps

We prepare CEIG files in-house: drawings, calculations, test records and the completion report, alongside the DISCOM net-metering application. For Tamil Nadu we would check the Inspectorate's current documents and fee schedule with its office before filing, as the rules above are the state's own and change by notification. Solar and MEPF can run under one contract. Our project list includes a 120 kW rooftop plant at Bindal Agencies in Chennai on a metal-sheet roof (project page). We work from offices in Noida (Delhi NCR) and Ludhiana, with 535+ projects across 18+ states and 89.77% repeat clients. We review files and design; we do not sell audits.

Send us your single-line diagram, layout and load sanction and we will review the file against the points above before you submit it. See our CEIG approval consultancy, message us on WhatsApp, call +91 70099 85817, or ask for a free proposal.